Stack controlling overhead belt box dumpers



July 19, 1955 E. A. VERRINDER 2,713,430

STACK CONTROLLING OVERHEAD BELT BOX DUMPERS Filed July 28, 1950 5 Sheets-Sheet l INVENTOR.

ERNEST A. VERRINDER A T TOR/VE Y July 19, 1955 E. A. VERRINDER 2,713,430

STACK CONTROLLING OVERHEAD BELT BOX DUMPERS Filed July 28, 1952 Sheets-Sheet 2 I42 M 139 I 86 I28 I28 I23 I (,7

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,6 6 a 68 3 3G F/G. 2 2 (a0 "49 55 5| ZOO INVENTOR.

ERNEST A. VERR/NDER A T TORNE Y July 19, 1955 E. A. VERRINDER STACK CONTROLLING OVERHEAD BELT BOX DUMPERS Filed July 28, 1950 INVENTOR. ERNEST A. VEfiR/NDER E A TTOR/VEY July 19, 1955 E. A. VERRINDER STACK CONTROLLING OVERHEAD BELT BOX DUMPERS 5 Sheets-Sheet 5 Filed July 28 1950 INVENTOR. ERNEST A. VERRINDER ATTORNEY STAQK {IUNTRGLLENG UVERHEAD BELT BQX DUMPERS Ernest A. Verrinder, Riverside, (:alif assignor to Machinery and Chemical Corporation, San .lose, Cairn,

a corporation of Delaware Application July 28, 85h, fierial No. 132,924

1.0 'llaims. (Q5. fi t -3%) This invention relates to the art of handling a product in bulk in open top boxes and is particularly useful in dumping the contents from such boxes.

This application covers an improvement in the box dumper shown in my co-pending application for U. S.

Letters Patent Serial No. 168,789 filed June 17, 1950.

In that application I disclosed an overhead belt box dumper for dumping stacks of boxes in which a stack was lifted at a fairly steep angle to a device for dumping each box in the stack at a relatively high level above the floor along which the stacks were fed into the ma chine.

A distinguishing feature of the invention disclosed in said co-p-ending case was the employment of an overhead belt which the boxes of the rising stack successively engaged. This belt rolled each box engaged thereby over an arched fulcrum plate to dump the contents from the box and to deliver the box, thus emptied, onto an empty box conveyor.

In packing houses, canneries and the like, it is often an advantage to be able to dump the loose product from the boxes of stacks delivered in upright position to the machine at a somewhat lower point than heretofore found practical for stacks so delivered.

It is accordingly an object of the present invention to provide an overhead-belt box dumper which is adapted to receive vertical stacks of boxes brought thereto on a horizontal floor track and dump the contents from the boxes so that said contents leave the box at a substantially lower level than has hitherto been possible with stack dumpers to which stacks are fed in this manner.

A further object is to provide such an overhead-belt stack dumper which is readily adjustable to vary the level at which the contents of the individual boxes are dumped therefrom.

It is another object of this invention to provide an overhead-belt stack dumper in which the overhead belt frictionally engages the uppermost box of a stack being fed into the machine and maintains such engagement so as to control the tilting of said stack towards a reclining position against the stack elevator of the machine, thereby permitting said elevator to be inclined at a substantially greater angle from vertical than previously possible, and at the same time accomplish the dumping of each box at the upper end of the elevator by engagement of said belt therewith.

The manner of accomplishing the foregoing objects, as well as further objects and advantages, will be made manifest in the following description taken in connection with the accompanying drawings in which:

Fig. 1 is a side elevational view of a preferred embodiment of the stack controlling overhead belt box dumper of this invention showing the overhead belt controlling the tilting of a stack.

Fig. 2 is a front elevational View of Fig. l taken in the direction of the arrow 2.

Fig. 3 is a fragmentary diagrammatic sectional view, of reduced scale, taken on the line 3-3 of Fig. 2 and nited Sates Patent "ice illustrating a step in the operation of the invention closely following the step illustrated in Fig. 1.

Fig. 4 is a view similar to Fig. 3 showing a step in the operation of the invention just in advance of that shown in Fig. 3, and in which the uppermost box of the stack is being readied over the dumping fulcrum to dump the contents therefrom.

Fig. 5 is a view similar to Fig. 4 and illustrating a further advance step in the box dumping operation wherein the box has been rolled and the engagement with the empty box conveyor.

Fig. 6 is a view similar to Fig. 5 and illustrates a still further advance step in the dumping operation in which the completely empty box has been delivered onto the empty box conveyor and showing the overhead belt rig strung upwardly to accommodate the discharge of the empty box onto the empty box conveyor.

Fig. 7 is an enlarged fragmentary operational View taken on the line 3-3 of Fig. 2 of a stack lifting cradle preferably employed in the stack elevator of the invention, this view showing the cradle as it approaches its uppermost position.

Fig. 8 is a View similar to Fig. 7 and illustrates said cradle as it bypasses roller traps just before it reaches its uppermost position.

Fig. 9 is a view similar to Fig. 8 illustrating a still further advanced stage in the progrcss of the elevator cradle as it turns about the elevator drive shaft at the upper end thereof.

Fig. 10 is a view similar to Fig. 9 and illustrates said cradle being cammed into its fully retracted position by engagement with said drive shaft.

Referring specifically to the drawings, the invention is therein shown as embodied in a stack conveying and elevating, and box dumping apparatus 15, which is mounted on a main frame comprising a pair of heavy angle iron members l6, supported on a floor 17. The apparatus includes a stack conveyor 18, a stack elevator 19, a stack controlling and box dumping conveyor 20, a loose product conveyor 21 and an empty box conveyor 22.

The stack conveyor 18 includes a pair of endless chains 25 which turn around suitable sprockets 26 which are carried on stub shafts 27, the latter being journaled in bearings 28 mounted on the angle iron member 16. The chains 25 travel in channel-iron floor tracks 29 which are supported on floor l7 and are, therefore, horizontal. At the delivery end of the chains 25, the tracks 29 are inclined downwardly towards the pitch line of the sprockets 26 so as to produce a short downwardly inclined section 3% This is to cause each stack S of boxes B travelling on the stack conveyor 18 to rock towards the stack elevator 19 as this stack is about to be delivered to said elevator, the purpose of this being made clear hereinafter.

The stack conveyor 18 is driven by power applied to the chains 25 thereof under controls which regulate the delivery of stacks S to the elevator 19 so as to deliver each of said stacks in a timed relation with the operation of said elevator in a manner well known in the art and which is not, therefore, described herein in detail.

The elevator 19 comprises a rigid structure or stack elevator frame 35, including side standards 36 on which are formed bearings 37 which pivot on the shafts 27,

- said standards also having bolt holes 38 and being secured to the angle irons in by bolts 39 passing through a selected group of the holes 38 so that said angle irons form a base for the structure resting on the floor 17 and supporting the elevator 19. The selection of that group of the holes 38 through which bolts 39 pass determines the angle between the elevator 19 and the floor 17. The standards 36 are united in spaced relation Fixed on the standards 36 are upper and lower main bearings 43 and 49, res ectively, carrying a drive shaft and stub shafts 51. Fixed on the dr o sit sprockets 52 while the stub shafts carry uprockets 53. Trained about the sprockets 52 and 53 are endless elevator chains 54 on which are mounted a pair of V at) stack lifting cradles 55.

Each of the cradles 55 includes :1 ends of which are secured to corresp provided in chains Fixed on each s The up of arms 63 have bearir 's 65 hich rotatably receive a shaft 67, on the outer or dis of which are moun ed rollers 68 which travel between and are guided bv guides 42 and flanges 43, which also guide the r 1;; flights of chains 54. The upper ends of arms 65 are welded to a sleeve carrying a shaft 76, the opposite ends of which extend into slots 77 in side walls '78 of a stt k platform 79. The walls 78 carry bearings 3'3 at their rear ends which pivotally receive the shaft 67. The inner face of platform 79 is shaped to form a cam face 81 the purpose of which will be made clear hereinafter.

Applied to the outer faces of the flanges 43 are guide tracks 85 which terminate at their upper ends in cams 86, the purpose of which will be made clear hereinafter.

Also mounted on suitable bearings provided on the standards 36 is a stub shaft 87, carrying double sprocket 88, and a jack shaft 39 carrying a sprocket 9% on one end and a sprocket 91 on the other. The sprocket is connected by a chain 92 to the drive sprocket 93 of a geared motor unit 94.

An adjustable mounting 95 is provided one of the standards 36 for an idler sprocket 5 5. Fixed on the shaft 50 in the same radial plane with the sprockets 1 and 96 4;") and with the inner sprocket of double sprocket is a sprocket 97. Trained about this sprocket and the other sprockets aligned therewith (Fig. l) to effect rotation of shafts 5t) and 87 in opposite directions is an endless chain 98.

Pivoted on pins ill? provided on inner faces of standards 36 near their upper ends and yieldably held by springs 111 against pins 112 on said standards are roller traps 113 (Figs. 7 to 19).

The stack controlling and box dumping conveyor :3: is mounted on a head frame 129 comprising side elements 121 which include channel beams 122, to the lower edges of which are welded triangular plates 123, the latter being united by a transverse arcuatc plate 1% Lil M of a dumping fulcrum member 12", opposite ends of tin which plate are welded to plates 123. The plate 124 is preferably covered by a sheet of ponge rubber 126, which is cemented thereto.

The lower corners of plates 1 by bolts 12% to the bearings 4-6 for d outwardly from upper ends of the elevator stander 36. Each of the elements 121 also includes tubular sockets 13%, the purpose of which will be made clear hereinafter.

Pivotally connected at its opposite ends to the lugs 47 and to the front ends of beams 122 are turnbuckles 131 by the adjustment of which the angular relation between the conveyor Zll and the elevator .19 may be determined. Welded upon the forward ends of beams I122 are beam sections 132 carrying bearing supports 133 on which are mounted bearings 13 3 in which a shaft 135 is otally secured by shafts Zoo and journaled. The near end of shaft 135 as seen in Fig. l carries the sprocket 136, which is radially aligned with the outer sprocket of double sproce..t 38 and is connected thereto by an endless chain 137 which is trained about these two sprockets.

Pivotally mounted at their opposite ends on the shaft 135 and a shaft 138 spaced horizontally therefrom are spacer members 139. These carry adjustable collars 14d, 14d and 142. Depending from collars 149 are supporting posts 143, the lower ends of which extend into the sockets and carry adjustable collars 144, which may be fixed on these posts in various positions to determine the height to which these posts support the members 139, and the shaft 138 carried thereby, above the upper end of the elevator 19.

Fixed on the shafts and 133 are pairs of spaced pulleys and 15?. about which are trained a pair of spaced endless belts 152. Disposed within these belts are a pair of belt tensioning rollers 153 and 154, carried 156. Shaft 155 is supported at its opposite ends between lower ends of arms 158 having a series of holes 159 which may be used optionally to receive opposite ends of a shaft 60 which pivotally connects said arms 158 to collars 142. Opposite ends of coiled contractile springs and 162 are attached to the head frame elements 12;". and to lower ends of the arms 15? and 158 so to yieldably press the rollers 153 and 154- downwardly against the lower flights of the endless belts 3.52.

ose product conveyor 21 is diagrammatically 1 the drawings in order that adjacent portions of ture of the invention would not be obscured. iveycr includes an enlcss belt Hi3, which is trained about pdleys 191. "'lLl 1.2, the receiving end of this conveyor ext adin th a, discharge edge 193 of .1 125 1g in the direction of the to rapidly convey away loose product it to be on stood, of course, that the conveyor is provided VllLll side wal loose product on the belt 12* ing conveyed away.

The empty box conveyor 22 comprises a pair of roller conveyor sections which are welded to the channel members 122 and eaten inwardly therefrom, these conveyor sections carrying rollers E97 upon which boxes E, emptied of their contents, adapted to travel open top down.

frovided on rear edges of standards 36 is a cross member having a re ker Elli which extends into the path of each descending cradle 55 so as to be swung by the shaft at? of said cradle and thus cngag the cam 83. thereof and swing the cradle to its forward position in readiness-to lift a stack 5 when it starts upward with the rising flights of chains 54.

Operation ted by the arro belts er box ll of the stack S by the sprn with sufficient pressure to cause these belts to centre the further tilting of the stack 5 so that this i box of the stack rith belts E52 until on in parallelism with and reclining against the rigid structure 35 of the elevator The relation of the boxes 8 of stack S to the elevator 19, at the moment the stack is thus delivered into a position of rest on the elevator structure, is shown in Fig. 3. Here it is seen that the upper two boxes of the stack have engaged the cams 86 provided on the standards 36 so as to effect a shift between these two boxes and the remainder of the stack. The delivery of stack S to the elevator 19 in this manner was timed by the controls heretofore mentioned but which are not shown herein so that one of the cradles 55 is just approaching this stack beneath and rising upwardly to engage the same as shown in Fig. 1, whereas the other of these cradles is just being withdrawn rearwardly out of the Way of the incoming stack as is shown in Fig. 10. If the withdrawal of the upper cradle 55 has not been completed by the time the new stack S is delivered to the elevator 19, the engagement of the upper boxes of this stack with the platform 79 of the upper cradle propels the s latter rearwardly into alignment with the balance of the upper cradle as shown in Fig. 3.

The manner in which the upper cradle 55 is retracted into the position in which it is shown in Fig. 10 is illustrated in Figs. 7, 8, and 9.

Fig. 8 illustrates the upper cradle 55 as it is just arriving at the uppermost point in its travels where the lowermost box of a stack just elevated thereby is being delivered to the stack controlling the box dumping conveyor 29 for dumping the contents therefrom as will be described hereinafter. In this view the rollers 68 are shown swinging the roller traps 113 away from the pins 112, following which, the springs 111 return these traps beneath said rollers so that, as the shaft 60 of this cradle passes on over the shaft 59 as seen in Fig. 9, the rollers 68 ride on top of the roller traps 113 and ultimately come to rest against the flanges 44 as shown in Fig. 10. The engagement of the arm 65 with the shaft 50 as shown in this view swings these arms rearwardly whereby the platform 79 is overbalanced and falls back to a position where the arms contact the shaft 76 which retains the parts of this cradle 55 in alignment while it descends as shown in Fig. 3. 1

As the stack S is lowered or tilted by the belts 152 into a reclining position on the tracks 85 and earns 86 provided on the standards 36, the cradle 55 rising therebeneath engages the lowermost box on this stack and starts to elevate the stack. This upward movement continues while each of the boxes B of the stack is, in turn, pressed against the belts 152 and rolled by these over the dumping fulcrum member 125 so as to discharge the contents of the box over this fulcrum member and onto the loose product conveyor 21, and discharge the empty box onto the empty box conveyor 22. The topmost box of a new stack being delivered into the machine is tightly engaged by the belts 152 as shown in Fig. 1 to control the tilting of the stack into parallelism with the elevator 19 and reclining thereagainst, and the rolling of this uppermost box over the fulcrum member 125 commences immediately upon the stack reaching this position of rest against the elevator which also approximately coincides with the engagement of the lower cradle 55 with the bottom of the stack and the start of the continuous upward movement of the latter riding upon this cradle.

From the point in the operation of dumping the boxes of the stack shown in Fig. 3, the topmost box is rolled between the belts 152 and the fulcrum member 125 through the position in which this box is shown in Fig. 4

until most of the loose product in the box is dumped therefrom as shown in Fig. 5 and the box has been brought into contact with the initial pair of rollers 197 of the empty box conveyor 22. The belts 152 at this point contact one of the bottom corners of the box and as they progress press it against the empty box conveyor 22 and further invert the box, discharging the balance of the loose product therefrom onto the downward sloping discharge portion of the fulcrum member as the box is lifted upwardly almost entirely inverted on the empty box conveyor 22 (Fig. 6).

It is necessary to lift the free end of the stack controlling and boxdumping conveyor 20 to permit the empty box to pass between this and the empty box conveyor 22. When this occurs, the posts 143 are withdrawn slightly from their fixed sockets 130, the amount of this withdrawal being indicated by the height of the collars 144 in Fig. 6 above the upper ends of the sockets.

Fig. 6 also shows the next upper most box in the stack engaging the lower flights of belts 152 While the empty first uppermost box is still holding the free end of the conveyor 20 upwardly. As soon as the pressure between the lower flights of the belts 152 against the upper near corner of the now uppermost box in the stack is suflicient, these belts will start to rock this box over the fulcrum member 125 so as to dump the contents therefrom in the same manner as occurred in the dumping of the first uppermost box above described. In this way, each of the boxes of the stack is in succession rolled between the conveyor 20 and the fulcrum member 125, the contents dumped therefrom and the empty box then discharged onto the empty conveyor 22.

As may readily be seen from the side elevational view of Fig. l of the apparatus 15 and from the above description of the operation thereof, this invention permits the delivery of fruit dumped from the boxes at a substantially lower elevation above the floor 17 than would be possible without the control of the tilting of the stacks S into parallelism with the stack elevator 159 which is effected by the engagement of the topmost box of the stack with the lower flights 179 of the belts 152 of the stack controlling and box dumping conveyor 20.

While I prefer to employ a pair of spaced belts 152 in the conveyor 20 for controlling delivery of stacks S to the elevator 19 and for then rolling boxes of the stack successively to dump the same, these functions can be performed with a single belt of a width greater than the length of a box B. In claiming the conveyor 20 broadly therefore the term belt may be used in a generic sense to refer to either a pair of belts 152 or to a single belt as noted substituted therefor and having the same general mode of operation and functions as the two belts 152.

The stack dumper 15 is adjustable to vary the level at which the contents of the boxes B are dumped by changing the angle between the elevator 1 and the floor 17, and

changing the angle between the elevator 19 and the box dumping conveyor 26. These changes are elfected by removing bolts 39 (Fig. l) and replacing them in a different selected group of the holes 38, and by altering the length of turnbuckles 131.

Briefly summarizing the specific structure of the illustrated embodiment of the invention: floor mounted angle members 16 support and are adjustably secured to frame 35 of stack elevator 19 by bolts 3% in a rearwardly inclined position which can be modified by repositioning said bolts. Stack conveyor 13, operating in timed relation with elevator 19, delivers thereto upright stacks of loaded open top boxes upwardly disposed. The rearward inclination of the elevator requires each stack to be gently tilted and lowered into a position of rest thereagainst before being elevated. Head frame 120 includes vertical side members 121 comprising beams 122, triangular plates 123, beam sections 132, and bearing supports 133. Bolts 128 pivotally mount head frame 12% on the upper end of elevator 19. Turnbuckles 131 also connect elevator 19 to head frame 126 and permit ready adjustment of their angular relation to match a corresponding adjustment by bolts 39 of the inclination of elevator 19 relative to horizontal. Mounted on head frame 120 at the upper end of elevator 19 and rearward of the stack elevating path is a box dumping fulcrum 124 J opposite ends of which are welded to plates l23. Empty box conveyor 22 is welded to rear ends of head frame beams 122. Bearings 134 on supports 333 journal shaft 135 by which overhead belt conveyor is pivotally mounted on head frame 120 and by which it is also driven. Spacer members 139 pivot at their opposite ends on sh 135 and 133 which carry drive and driven pulleys 1 and 1.51 of conveyor 2%. Considering endless belts 152 trained about these pulleys as a single belt, this may be said to have a lower flight 17% which is yieldably depressed independently at longitudinally spaced po" LS by rot 153 and 154 mounted on arms 157 and 15?; depent from spacers 139, and swung downward by springs 161 and 1&2 lower ends of which are attached to head frame The downward swinging of overhead belt it about shaft 135 is adjustably lim by co fixed on supporting posts upper ends wlu 1 at 1 5 to pulley spacer members 139 and the hwer ends of which are guided in sockets 13% welded head frame beams 122. Thus it is seen that the angle of inclination between the floor and the stack elevator 19 is adjustable by moving bolts 39. The angular relation between stack elevator 19 and head frame 126 about bolts 128 is adjustable by turnbuckles 13L The minimum cing of the overhead belt conveyor 29 from the dumping fulcrum 124 and from empty box conveyor 22 is adjustable by shifting collars 144 or. support rods M3 thereby swinging conveyor 2% about snaft .535 relative to head frame 120.

The claims are:

1. A box dumping device, comprising: a stack conveyor for moving upright stacks of loaded open-top boxes in a horizontal direction; a stack elevator inclined toward the rear of said device and disposed to receive and elevate said stacks in sequence; a fulcrum member mounted to the rear of and at the upper end of said stack elevator; a stacktilting and box-dumping conveyor including horizontally spaced pulleys and an endless belt trained thereabout, said belt conveyor being disposed above said stack elevator in alignment with the direction in which the stocks are delivered thereto, said belt conveyor having a front portion the lower flight of which partially overlies said stack conveyor and is upwardly inclined forwardly to initially be engaged by the nearest upper corner of the uppermost box of the stack being delivered to said stacl; elevator; means driving said belt conveyor with said lower flight traveling in the same direction as and at a faster rate than said stack conveyor; and means yieldably pressing said traveling lower flight downwardly into frictional engagement with said upermost box to tilt said stack rearwardly into position against said stack elevator, said yieldable means then continuing to press said lower flight downwardly against said uppermost box of the tilted stack whereby said lower flight in traveling, rolls said box over said fulcrum member to dump its contents, said stack elevator raising the remainder of the boxes of said tilted stack suc essively into frictional contact with said moving lower flight, thereby causing each box to be dumped by rolling it over said fulcrum member as aforesaid.

2. A combination in claim 1 having elevator mounting means for adjustably varying the angular inclination from horizontal of said stack elevator; a head frame pivotally mounted on the upper end of said stack elevator, said head frame having mounted thereon said fulcrum member, said belt conveyor and said means for yieldably pressing said lower bclt flight downwardly; and means for adjustably varying the angular relation between said stack elevator and said head frame, in order to maintain the latter in approximately the same angular relation to horizontal for ditterent angular inclinations therefrom in said stack elevator.

3. A combination as in claim 2 in which said belt con- Q.) veyor is pivotally mounted near its front end on said head frame to permit said belt conveyor to swing upward about the axis of said mounting in response to upward pressure of said boxes thereagainst.

4. A combination as in claim 3 in which said yieldable pressing means comprises roller means applied to the conveyor belt lower flight and spring means connecting said roller means with said head frame so that said yieldable means not only presses said lower flight downwardly but res' ard swinging of said belt conveyor about its mot n is.

5. A combination as in claim 4 having means to adjustably limit the downward swinging of said belt conveyor about the axis of its mounting on said head frame to vary the minimum spacing between said lower belt flight and said flllCl'Ul l member.

6. A coml illOll as in claim 1 in which means is provided for pivotally mounting said belt conveyor about a fixed axis near its front end to permit said belt conveyor to swing upward about said axis in response to upward pressure (if said boxes thercagainst.

7. A combination as in claim 6 having means to adjustably limit the downward swinging of the belt conveyor about the axis of its mounting to vary the minimum spacing between said lower flight and said fulcrum memher.

8. A combination as in claim 1 in which said means for yieidably pressing the belt conveyor belt lower flight downward is applied to said lower flight principally in the area thereof intersecting the inclined stacl: elevating path, and in which combination said lower flight inclines upwardly between path and the rear end of said belt conveyor; and an empty box conveyor mounted under and in closely spaced relation with said rearwa'd upwardly inclining portion of said lower flight whereby a box just emptied by being rolled over said fulcrum member by said lower flight is propelled by said flight against and upwardly onto said empty box conveyor.

9. A combination as in claim 8 in which means is provided for pivotally mounting said belt conveyor about a fixed axis near its front end to permit said belt conveyor to swing upward about said axis in response to upward pressure of said boxes thercagainst; and means to adjustably limit the downward swinging of said belt conveyor about the axis of its mounting to vary the minimum spacing between said lower flight, on the one hand, and said fulcrum member and empty box conveyor on the other.

10. A combination as in claim 9 having elevator mounting means for adjustably varying the angular inclination from horizontal of stack elevator; a head frame pivotally mounted on the upper end of said stack elevator, said head frame having mounted thereon said dumping fulcrum, said empty box conveyor, said belt conveyor and said means for yield-ably pressing said lower flight downwardly; and means for adjustahly varying the angular relation between said stack elevator and said head frame in order to maintain the latter in approximately the same angular relation to horizontal for different angular inclinations therefrom in said stac; elevator.

References Cited in the file of this patent UNETED STATES PATENTS 

